1. Technical Field
The present invention generally relates to an apparatus and method for stabilizing the output sequence of a real random number generator and, more particularly, to an apparatus and method for stabilizing the output sequence of a real random number generator that is used in security systems.
2. Description of the Related Art
The core of a real random number generator for generating an output sequence (key sequence) is to provide statistical randomness. Generally, a real random number generator uses unpredictable, uncopyable, and non-deterministic noise sources that may be extracted from a natural phenomenon.
A real random number generator that uses an analog noise source may generate biased random numbers due to a surrounding environment or device aging.
That is, since the characteristics of a real random number generator change every moment, the entropy of an output sequence may be decreased.
In other words, if a surrounding environment and condition are satisfied, such a real random number generator generates unbiased random numbers, but if the surrounding environment is deteriorated or aged, predictable random numbers having a specific pattern may be generated. In this case, security systems that use predictable random numbers become vulnerable to external attacks.
As related preceding technology, Korean Patent Application Publication No. 2004-0085608 (entitled “Method and Apparatus of Generating Random Number Using Electronic Circuit Noise”) discloses technology that provides statistical randomness suitable for a random number generation apparatus implemented using hardware including electronic circuits.